Saint Michael's Church is the oldest extant religious site in Luxembourg City. The first church was built on the site in 987 as the castle chapel for the Count of Luxembourg. However, over the following centuries, the building was destroyed, rebuilt, and renovated several times. Its current appearance dates to 1688, and unites Romanesque and Baroque architectural styles, pre-dating the national Moselle Baroque style. The building has been restored since then, preserving its original form.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.